From December 1994 to October 1995, the rotifer fauna of a shallow lake in north-west Germany, the "Dümmer", was investigated. Quantitative sampies were taken at seven sampling sites, some of which were at points along t

From December 1994 to October 1995, the rotifer fauna of a shallow lake in north-west Germany, the "Dümmer", was investigated. Quantitative sampies were taken at seven sampling sites, some of which were at points along the shore and others from the centre of the lake. The results show a high identity of species between all collected probes. Differences between the sam pie sites near the lake's shore and from the free water were noticed in abundance dynamics and dominance structure. A final comparison with earlier investigations shows a turnover of species of the rotifer fauna during the last 45 years.